Difference Between Mid-Pipes?

Anyone know the difference between an 87-93 x or h pipe and ours on 94-95's?

I found a guy selling one that he pulled off of his 91GT but, it seems as though the 87-93 and 94-95 have different part numbers. Just wondering how much different they are.

Thanks for any help.
 
IIRC the only difference is ours has the port for the smog tube and the fox's do not. I believe fox's headers are the same except the EGR exhaust bung as well.

But do some searching on this forum first on here to confirm what I say before you buy. I am not 100% sure. I know there has been threads about this.
Scott